N-th member of arithmetical progression

Members of of an arithmetical progression and arithmetic average

Sum of the members of an arithmetic progression (arithmetic series)

Sum of the members of an arithmetic progression (arithmetic series)

N-th member of geometric progression

Members of geometric progression and geometric average

Sum of the members of geometric progression (geometric series)

Sum of the members of geometric progression (geometric series)

Sum of an infinite geometric progression (infinite geometric series)

a1 - first member

d - common difference of an arithmetical progression

n - member number

d - common difference of an arithmetical progression

n - member number

Find
It is known that:

=

Members of of an arithmetical progression and arithmetic average

a_n - n-th member

a_M1 - (n-1)-th member

a_P1 - (n+1)-th member

a_M1 - (n-1)-th member

a_P1 - (n+1)-th member

Find
It is known that:

=

Sum of the members of an arithmetic progression (arithmetic series)

a1 - first member

d - common difference of an arithmetical progression

n - member number

d - common difference of an arithmetical progression

n - member number

Find
It is known that:

=

Sum of the members of an arithmetic progression (arithmetic series)

a1 - first member

a_n - n-th member

n - member number

a_n - n-th member

n - member number

Find
It is known that:

=

N-th member of geometric progression

b1 - first member

q - common ratio of a geometric progression

n - member number

q - common ratio of a geometric progression

n - member number

Find
It is known that:

=

Members of geometric progression and geometric average

b_n - n-th member

b_M1 - (n-1)-th member

b_P1 - (n+1)-th member

b_M1 - (n-1)-th member

b_P1 - (n+1)-th member

Find
It is known that:

=

Sum of the members of geometric progression (geometric series)

b1 - first member

q - common ratio of a geometric progression

n - member number

q - common ratio of a geometric progression

n - member number

Find
It is known that:

=

Sum of the members of geometric progression (geometric series)

b1 - first member

b_n - n-th member

n - member number

b_n - n-th member

n - member number

Find
It is known that:

=

Sum of an infinite geometric progression (infinite geometric series)

b1 - first member

q - common ratio of a geometric progression

q - common ratio of a geometric progression

Find
It is known that:

=